EP0087281A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of constructing holograms
Assignee: Fujitsu Ltd
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Filing: 1983-02-18
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Granted: —
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Expires: 2003-02-18
Abstract
Abstract A method of constructing a hologram comprises providing a master hologram (12) consisting of a predetermined pattern of interference fringes formed thereon by optical interference of a plurality of constructing coherent light beams incident at different angles; preparing a photosensitive medium (15), in which the hologram is to be formed, on the master hologram; and copying the master hologram onto the photosensitive medium (15) by impinging copying light beams (16) on the master hologram at incident angles different from those of the constructing beams.
Inventors
- 👤 Hiroyuki Ikeda
- 👤 Fumio Yamagishi
- 👤 Shinya Hasegawa
- 👤 Syunji Kitagawa
- 👤 Kozo Yamazaki
- 👤 Takefumi Inagaki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 23:03
CPC Classifications
G; G03; G03H; G03H1/00; G03H1/02; G03H1/024; G03H1/0248; G03H1/04; G03H1/20; G03H1/202; G03H1/0005; G03H1/26; G03H1/2645; G03H1/265; G03H2001/205; G03H2001/2605; G03H2001/261; G03H2001/2615; G03H2222/00; G03H2222/36; G03H2250/00; G03H2250/12; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
174 words
1 . A method of constructing a hologram, the method comprising providing a master hologram plate (12) which has a base plate (11) with a master hologram consisting of a predetermined pattern of interference fringes formed thereon by optical interference of a plurality of constructing coherent light beams incident upon the base plate at different angles; preparing a photosensitive medium (15),in which the hologram is to be formed,on the master hologram plate; and copying the master hologram onto the photosensitive medium (15) by impinging a copying light beam (16) on the master hologram at an incident angle different from those of the constructing beams, so that the copying light beam produces transmission beams (18) passing through the associated interference fringes of the master hologram and first-order diffraction beams (17) diffracted by the associated interference fringes of the master hologram, whereby a desired copy hologram having the same pattern of interference fringes as the master hologram is constructed in the photosensitive medium (15) by optical interference of the transmission beams and the first-order diffraction beams.
Claim 2
Dependent Claim
174 words
1 . A method of constructing a hologram, the method comprising providing a master hologram plate (12) which has a base plate (11) with a master hologram consisting of a predetermined pattern of interference fringes formed thereon by optical interference of a plurality of constructing coherent light beams incident upon the base plate at different angles; preparing a photosensitive medium (15),in which the hologram is to be formed,on the master hologram plate; and copying the master hologram onto the photosensitive medium (15) by impinging a copying light beam (16) on the master hologram at an incident angle different from those of the constructing beams, so that the copying light beam produces transmission beams (18) passing through the associated interference fringes of the master hologram and first-order diffraction beams (17) diffracted by the associated interference fringes of the master hologram, whereby a desired copy hologram having the same pattern of interference fringes as the master hologram is constructed in the photosensitive medium (15) by optical interference of the transmission beams and the first-order diffraction beams.
Claim 3
Dependent Claim
20 words
A method according to claim 1, wherein the photosensitive medium (15) comprises a photosensitive layer directly coated on the-master hologram.
Claim 4
Dependent Claim
47 words
Amethod according to claim 1, wherein the photosensitive medium comprises a copy hologram base plate (13) which has a photosensitive layer (15) coated thereon and which is superimposed on the master hologram plate so that the photosensitive layer comes in close surface contact with the master hologram.
Claim 5
Independent Claim
25 words
A method according to any of claims 1 to 3, wherein the copying beam:(16) is incident upon the master hologram at an angle perpendicular thereto.
Claim 6
Independent Claim
46 words
A method according to any of the preceding claims, wherein the copying beam (16, 20) has incident angles identical to those of the transmission beams with respect to the photosensitive medium or identical to those of the first-order diffraction beams with respect to the photosensitive medium.
Claim 7
Independent Claim
42 words
A method according to any of claims 1 to 4, wherein the copying beam has incident angles equal to incident angles of the transmission beams and the first-order diffraction beams at which the two kinds of beams have a same diffraction efficiency.
Claim 8
Independent Claim
75 words
A method according to any of the preceding claims, further comprising coating a filtering layer (50) on the master hologram prior to the provision of the photosensitive medium (15) onto the master hologram plate, the filtering layer having a transmittance which decreases as the incident angle of the beams incident thereupon with respect to a line perpendicular to the filtering layer increases selectively to interpept the beams having an incident angle above a predetermined value.
Claim 9
Independent Claim
17 words
A method according to any of the preceding claims, wherein the copying beam (16) comprises spot-like beams.
Claim 10
Independent Claim
26 words
A method according to any of claims 1 to 7. wherein the copying beam (16) has a predetermined width of beams impinging over the master hologram.
Claim 11
Dependent Claim
27 words
1 0. A method according to any of the preceding claims, wherein the copying beam (16) and the master hologram plate are moved relatively to one another.
Claim 12
Dependent Claim
33 words
A method according to claim 10, wherein the master hologram plate (12) is moved in two-dimensional directions, together with the photosensitive layer (15) for the copy hologram, relative to the copying beam (16).
Claim 13
Independent Claim
123 words
A method according to any of the preceding claims, further comprising, subsequent to preparing the first copy hologram, preparing a second photosensitive medium (15"), in which a seoond hologram i.e. the desired hologram is to be formed, on the first copy hologram (15'); copying the first copy hologram onto the second photosensitive medium (15") by',impinging. a second copying light beam (16B) on the first copy hologram at an incident angle different from those of the constructing beams and from that of the first copying light beam (16A), so that the desired hologram having the same pattern of interference fringes as the master hologram is constructed in the seoond photosensitive medium (15") in a similar way to the construction of the first copy hologram.
Claim 14
Dependent Claim
39 words
A method according to claim 12, comprising repeating the copying steps in which a copy hologram constructed in the preceding copying step is used as a master hologram which is to be copied to construct a succeeding copy hologram.
Claim 15
Dependent Claim
12 words
A copy hologram prepared in accordance with any of the preceding claims.
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